The present invention is directed to applicator wands for cleaning finned coils in HVAC installations including particularly the coils located in outdoor, rooftop and attic HVAC units and coils located where electricity is usually not available.
A typical HVAC installation for residential and commercial buildings includes an outdoor condenser unit having heat exchange coils, indoor evaporator units having heat exchange fin and coil combinations with water condensate collection trays and drain lines located in ductwork, and air handling components.
Outdoor condenser coils are arranged in banks at the outer periphery of a condenser unit and are cooled with ambient air drawn through the coils by an electric fan. In operation, the coils accumulate deposits of pollen, grass clippings, insects, and so forth carried by ambient air drawn through the coils. In addition, the outdoor condenser coils develop an oxidized film or coating that diminishes heat exchange efficiency and requires periodic removal by chemical cleaning of the coil surface.
For optimum operating efficiency of HVAC installations, heat transfer coils must be cleaned from time to time of such deposits and coatings that build-up in normal operation and by natural processes (i.e., oxidation) with passage of time. The present invention provides an apparatus and method especially suited for cleaning outdoor coils in an effective manner so as to remove accumulated deposits and coil films or coatings which are detrimental to HVAC operating efficiency. The invention may be used for a routine maintenance schedule that checks building operating costs by ensuring thermal efficiency and extending the useful operating life of HVAC installations.
Copending U.S. application Ser. No. 12/283,083 filed Sep. 9, 2008 provides an apparatus containing all components and consumable cleaners including water and chemical for cleaning HVAC coils situated in tough to reach areas, and further provides a method for effectively cleaning such coils as well as applicator wands for spraying cleaners onto the coils. This application is directed to applicator wands disclosed in that application and added in this C-I-P application.